|Every 3 years, the National Cancer Institute (NCI) asks researchers,
advisory panels, and advocacy groups to recommend "extraordinary
opportunities for investment," which it defines as "broad-based,
overarching areas of scientific pursuit that hold tremendous promise for
significantly expanding our understanding of cancer." This is the third in a series of interviews exploring the progress and
promise of NCI’s six current extraordinary opportunities: Genes and the
environment; cancer imaging;
defining the signature of cancer cells (below); molecular targets of prevention
and treatment; research on tobacco and tobacco-related cancers; and cancer
BETHESDA, MarylandAs researchers probe the complex nature of individual
cancer cells, unique molecular patterns, or signatures, have emerged. Several
drugs based on early findings in the field have already earned US Food and Drug
Administration approval. A goal set by the National Cancer Institute (NCI) is
to "catalog distinguishing molecular signatures of cancer cells to develop
new diagnostic and therapeutic approaches and predict response."
Dr. Robert L. Strausberg, PhD, director of NCI’s Cancer Genomics Office,
discussed the Institute’s extraordinary opportunity in signature research
with ONI Washington bureau chief Patrick Young.
ONI: Would you define what NCI means by the signatures of cancer cells?
Dr. Strausberg: Traditionally, we have defined cancer by body location and
various features that can be seen under the microscope. When we talk about
signatures, we are talking about understanding the molecular events that
distinguish one cancer cell from other cancer cells and from normal cells, and
using changes in the genetic blueprint to identify a unique signature that tells us
how that cancer cell is different. That allows us, for example, to distinguish
different types of breast tumors.
ONI: Can you give me a specific example of a cancer signature?
Dr. Strausberg: I will give you several. Gleevec [imatinib mesylate], whose
development for CML [chronic myelogenous leukemia] predates NCI’s
extraordinary opportunity, was based on a chromosomal aberrationthe 9;22
translocation, or Philadelphia chromosome, which is seen in almost all cases of
CML. This is what we would call a molecular signature.
Going from that signature to actually having an intervention was a long
process. First, researchers had to determine if the translocation was involved
in the genesis of the cancer and also its maintenance. Then they could develop
a drug that targeted the protein of that genetic region to treat the cancer.